1. Field of Invention
The present invention relates to a backlight module for a liquid crystal display (LCD) apparatus. More particularly, the present invention relates to a backlight module with detachable light source set.
2. Description of Related Art
The liquid crystal display (LCD) is an apparatus for displaying images by exploiting the characteristics of liquid crystal. The LCD is generally used in every kind of personal device nowadays, such as a mobile phone, a PDA, a digital camera, a television and a billboard, due to having more flexibility of application than traditional cathode ray tube (CRT) display with respect to size and weight.
An obvious difference between the principles of LCD and CRT displays is that the cathode ray tube of a CRT display can radiate light by itself, but the liquid crystal of the LCD cannot; that is to say, the CRT display can display images on the screen without an additional light source, but the LCD cannot. The LCD needs a backlight module in order to display images on the screen.
FIG. 1 shows an exploded structure of a conventional LCD. It can be seen that the LCD roughly comprises a bezel 102, a liquid crystal panel 104, a frame 106, an optical films set (including a diffuser plate) 108 and a backlight module 110. After the light radiated from the backlight module 110 passes through the optical films set 108, a uniform light source irradiating the liquid crystal panel 104 can be obtained. Thus the backlight module is a critical component in an LCD device.
Referring to FIG. 1, the backlight module comprises a back plate 112, a plurality of lamps 114, a lamp holder 116 and a driver circuit (not shown in the figure). The lamps 114 may be cold cathode fluorescent lamps (CCFL), which are arranged in parallel on the back plate 112; and the lamp holder 116 is used for fastening the lamps 114. The LCD is fabricated by stacking and fastening the frame 102, the liquid crystal panel 104, the bezel 106, the optical films set 108 and the backlight module 110 in order.
According to the foregoing components and manner of assembly, when the liquid crystal panel 104 displays images, the brightness will be insufficient or non-uniform if any one of the lamps 114 is damaged or broken, exhibiting poor-quality display. At that time, the damaged or broken lamp should be replaced. First, the backlight module 110 is disassembled from the LCD. Next, the lamp holder 116 is removed. Then, the damaged or broken lamp can be replaced. It can be seen that the replacement procedure is not only complex but also having a possibility of damaging other components near the replaced lamp, because the components, such as the other workable lamps, optical films set 108 and the driver circuit, are all very fragile.
Furthermore, replacing lamps in an LCD will become increasingly harder because of the tendency towards larger LCD. A backlight module where the backlight lamps can be readily replaced is certainly needed for the present LCD system.